Method for processing biomagnetic field data, magnetic field contour mapping, forming their waveforms and a biomagnetic instrument using the same

ABSTRACT

A method for processing biomagnetic fields generated by biocurrents resulting from activities of human brain or myocardia and its mapping apparatus are provided, which features biomagnetic measurement and its analysis, magnetic field mapping and its imaging and their waveform generation by a simple operation. Biomagnetic fields emitted from the patient are measured at a plurality of measurement positions, and a contour map of magnetic field obtained as a result of processing of these measured biomagnetic fields is imaged in the magnetic contour map display apparatus, which display apparatus comprises: the process function display area indicating process function items including measurement; and the analysis data display area which displays the waveform together with a designated measurement time, the waveform being generated during measurement at least based on the measured biomagnetic fields and during the designated measurement period of time.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a method of processingbiomagnetic fields generated by biocurrents resulting from activities ofhuman brain or myocardia, and its mapping system.

[0003] 2. Description of the Prior Art

[0004] There is known a prior art multi-channel bio magnetic fieldimaging system which uses a magnetic sensor of superconducting quantuminterference device (SQUID) in order to measure a weak magnetic fieldgenerated in the human body, estimates the positions of the sources ofits bio current from the result of measurement, and obtains itsdistribution as an image. Such prior arts are disclosed, for example, inJPA-4-319334 and 5-146416.

[0005] These prior arts are concerned with principles of operation ofthe biomagnetic imaging systems, and do not describe any particulartechnical problems to be solved or its specific method suitable forpractice. Further, the above-mentioned prior arts are related to thebio-activity currents generated in the brain, and do not disclose suchbio-active currents in other parts of the body.

SUMMARY OF THE INVENTION

[0006] An object of the invention is to provide a method for processingand analyzing measured data of the biomagnetic fields through a simpleoperation.

[0007] Namely, it is the object of the invention to provide the methodand a system using the same whereby a biomagnetic field map can beobtained easily from magnetic field intensities at a plurality of pointsof measurement, and in particular, to provide the method for displayingbiomagnetic field diagram and the system thereof, which can displayinformation changing with time or with reference to reference waveforms,and which is simple to operate.

[0008] It is another object of the invention to provide a biomagneticfield mapping display system which allows easy selection of anybiomagnetic field map and visual confirmation of items of selectionassociated with the selection thereof.

[0009] It is still another object of the invention to provide thebiomagnetic field map display system which can display an image whichchanges with time on real time.

[0010] It is still more object of the invention to provide thebiomagnetic field map display system which can eliminate noises fromrespective data obtained from measurements at respective channels.

[0011] The feature of the invention for accomplishing theabove-mentioned objects resides in that the method thereof comprises thesteps of: displaying plurality of points of measurement at which eachmagnetic field emitted from the patient is measured; specifying aparticular point of measurement from a plurality of displayed points ofmeasurement for displaying information on a result of its measurement;and displaying the information on the result of measurement at thespecified point of measurement, on the basis of its information stored.

[0012] Another feature of the method for displaying the information onthe result of measurements at specific points of the patient based onthe information stored according to the invention resides in that theinformation on the result of measurement is displayed on a display areawith respect to a time axis of abscissa corresponding to a designatedtime scale.

[0013] Still another feature of the method according to the invention,which comprises the steps of: measuring magnetic fields generated in thepatient at a plurality of points of measurement; and obtaininginformation on the results of measurements by processing the dataobtained at specified points based on its data stored, resides in thatthe same further includes the steps of: setting conditions of areference time; and averaging a plurality of data obtained at eachspecified point of measurement on the basis of the set-up conditions ofthe reference time.

[0014] Still more feature of the method of the invention, wherein thesame comprises the steps of: measuring magnetic fields generated in thepatient at a plurality of points of measurement; and processing data onthe result of measurements at any specified point of measurement on thebasis of its information stored, resides in that multiple data combiningmultiple results of measurements obtained at a plurality of points ofmeasurement are displayed in superposition on each other.

[0015] Still another feature of the biomagnetic field display systemaccording to the invention, which measures biomagnetic fields at aplurality of points of measurement and displays a magnetic field contourmap obtained by processing data on the result of the measurements,resides in that the same comprises: a process function indicationsection which indicates process function items including measurement;and an analysis data display section which forms waveforms which isproduced on the basis of measurements of biomagnetic fields during aspecified measuring time, then displays the waveform corresponding tothe specified measuring time.

[0016] Still more feature of the biomagnetic field display systemaccording to the invention, which measures biomagnetic fields at aplurality of points of measurement and displays a magnetic field contourmap obtained by processing data on the result of the measurements,resides in that the same comprises: a process function indicationsection which indicates process function items including measurement;and an analysis data display section which displays biomagnetic fieldsmeasured and a processed magnetic field obtained by processing the dataon the biomagnetic fields measured, resides in that said analysis datadisplay section has a scroll bar in the bottom portion thereof in whichscroll frames is movable are provided, and the waveforms displayed onthe analysis data display section can be enlarged to show an enlargedportion thereof corresponding to a time scale W in the scroll frame.

[0017] Still further feature of the biomagnetic field display systemaccording to the invention, which measures biomagnetic fields generatedin the patient at a plurality of points of measurement and displays amagnetic field map obtained by processing data on the result of themeasurements, resides in that the same comprises: a process functionindication section which indicates process function items includingmeasurement; and an analysis data display section which displaysbiomagnetic fields measured and a processed magnetic field obtained byprocessing the data on the biomagnetic fields measured, resides in thatsaid analysis data display section has an auxiliary channel or areference channel relating to its analysis data in the bottom portionthereof.

[0018] Still further feature of the invention resides in that a waveformdisplayed on the reference channel is a bio-activity waveform relatingto biomagnetic fields such as a cardiogram, brain waveform, blood streamand pressure waveform, or any of the magnetic fields indicative of thebiomagnetic field and the processed magnetic field displayed.

[0019] Still another feature of the biomagnetic field map display systemof the invention, which measures biomagnetic fields at a plurality ofpoints of measurement and displays its processed magnetic filed map, iscomprised of: a process function indication section for indicatingprocess function items including measurement; an analysis data displaysection for displaying a measured biomagnetic field and a processedmagnetic field obtained by processing the measured data; and anoperating region indication section for indicating operating itemscorresponding to its specific processing of the biomagnetic fields,wherein said analysis data display section displays the biomagneticfield or processed magnetic field corresponding to a channel defined bya row and column, said operating region indication section indicatesselection channel items, wherein said selection channel items arecomprised of channel items associated with the channel defined by therows and columns displayed on the analysis data display section, furthercomprising: a selection means for selecting said selection channel item;a display means for displaying a biomagnetic field or its processedmagnetic field corresponding to the selected channel item on saidanalysis data display section; and a means for identifying the selectedchannel item selected from said selection channels distinct from theother channel items.

[0020] Still further feature of a biomagnetic field diagram formingsystem according to the invention, which uses a SQUID which is amagnetic sensor to measure biomagnetic fields at a plurality ofpositions which are multi-channelled, and displays a magnetic fielddiagram obtained by processing the measured data, resides in that thesame further comprises; a time integral data forming means for forming atime integral data by integrating biomagnetic field data over apredetermined period of time and obtaining equivalent points in the dataobtained; and a time integral contour map display means for displaying acontour map of time integral based on the data obtained from the timeintegral data.

[0021] Still more feature of the biomagnetic field diagram formingsystem according to the invention, which uses a magnetic sensor of SQUIDto measure biomagnetic fields at a plurality of positions and displays amagnetic field diagram as a result of processing of the data obtained bythe measurements, resides in that the same comprises: an analysis datadisplay section for displaying measured biomagnetic fields and aprocessed magnetic field obtained by processing the measured datathereof; and an operation indication region for indicating operationalitems subject to data analysis, wherein said operation indication regiondisplay section displays items for entering an averaging mode andaveraging conditions, wherein said analysis data display sectiondisplays a biomagnetic field on a time axis and an averaging time forits biomagnetic field, and wherein its averaging condition set-upprocessing is executed with the display of its waveform to facilitatevisual observation.

[0022] Still more feature of the method of the invention, which includesthe steps of: measuring biomagnetic fields emitted from the patient at aplurality of points; and processing the data to obtain information onthe result of measurements obtained at designated points of measurementon the basis of its information stored, resides in that the same furthercomprises the steps of: setting a pitch between equivalent magneticfield contours; and displaying an equivalent magnetic field contourdiagram obtained by connecting a plurality of points each having anequivalent magnetic field strength at the designated pitch.

[0023] Still further feature of the method of the invention, includingthe steps of: measuring biomagnetic fields emitted from the patient at aplurality of points; and processing the data to obtain information onthe result of measurements obtained at designated points of measurementon the basis of its information stored, resides in that the same furthercomprises the steps of: displaying a waveform which changes with respectto the time axis; setting a plurality of periods of time on the timeaxis of the waveform; and displaying magnetic contour maps for thedesignated period of time.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024]FIG. 1 is a schematic diagram of a biomagnetic instrument of oneembodiment of the invention;

[0025]FIG. 2 is a perspective view of the arrangement of a magneticsensor for use in the biomagnetic instrument of FIG. 1;

[0026]FIG. 3 is a perspective view of a unit of magnetic sensor for usein the biomagnetic instrument of FIG. 1 and for detection of a normalcomponent of the magnetic field;

[0027]FIG. 4 is a perspective view of a unit of magnetic sensor ofanother embodiment for use in the biomagnetic instrument of FIG. 1 fordetecting a tangential component of the magnetic field;

[0028]FIG. 5 is a diagram indicating a positional relationship betweenthe magnetic sensors of the biomagnetic instrument of FIG. 1 and thechest portion of a patient;

[0029] FIGS. 6(A)-(C) are time waveform diagrams of respectivecomponents of biomagnetic fields (cardiomagnetic waveforms) measured fora healthy person by respective magnetic sensors in the biomagneticinstrument;

[0030]FIG. 7 is a diagram indicating tangential components ofmagnetocardiograph time waveforms at two channels specified and measuredfor a healthy person using the biomagnetic instrument of the FIG. 1;

[0031]FIG. 8 is a diagram indicating a basic layout of the screendisplayed on the display section in the biomagnetic instrument of FIG.1;

[0032]FIG. 9 is a diagram showing operation menu in the menu bar in thescreen displayed in the display section in the biomagnetic instrument ofFIG. 1;

[0033]FIG. 10 is a diagram showing the contents of a patientregistration dialog frame which is opened when “List (L) Registration(R)” are selected as operation menu in the screen displayed on thedisplay section in the biomagnetic instrument of FIG. 1;

[0034]FIG. 11 is a diagram showing the contents of a search dialog framewhich is opened when “List (L)-Search (S)” is selected as operation menuin the screen displayed on the display section in the biomagneticinstrument of FIG. 1;

[0035]FIG. 12 shows the contents of a manual adjustment dialog framewhich is opened when “measurement (Q)-Manual adjustment (M)” is selectedas its operation menu in the screen displayed on the display section inthe biomagnetic instrument of FIG. 1;

[0036]FIG. 13 shows the contents of an automatic diagnosis dialog framewhich is opened when “measurement (Q) Measurement panel (P)″ is selectedas its operation menu in the screen displayed on the display section inthe biomagnetic instrument of FIG. 1;

[0037]FIG. 14 shows the contents of a heat flash operation dialog framewhich is opened when “heat flash” button is clicked on the screen ofFIGS. 25 or 26 to be displayed on the display section of the biomagneticinstrument of FIG.

[0038]FIG. 15 shows a measurement progress bar which is displayed on thedisplay section during measurement in the biomagnetic instrument of FIG.1;

[0039]FIG. 16 is a schematic flowchart indicating the steps of operationexecuted in the biomagnetic instrument of FIG. 1;

[0040]FIG. 17 shows a patient selection flow of the patient selectionstep in the operation flow of FIG. 16;

[0041]FIG. 18 is a flowchart indicating the flow of measurement in themeasurement step in FIG. 16;

[0042]FIG. 19 is a flowchart indicating the flow of averaging in theaveraging operation step in FIG. 16;

[0043]FIG. 20 is a flowchart indicating the flow of data analysis in thedata analysis step in FIG. 16;

[0044]FIG. 21 is a diagram indicating the flow of system adjustment tobe executed in the biomagnetic instrument of FIG. 1;

[0045]FIG. 22 is a diagram indicating the flow of automatic averaging inthe automatic averaging step in the system adjustment flow of FIG. 21;

[0046]FIG. 23 is a diagram indicating the flow of Voff adjustment inVoff adjustment step in the system adjustment flow of FIG. 21;

[0047]FIG. 24 shows a patient list screen displayed on the displaysection of the biomagnetic instrument of FIG. 1;

[0048]FIG. 25 shows a measurement screen displayed on the displaysection of the biomagnetic instrument of FIG. 1;

[0049]FIG. 26 shows a confirmation dialog screen displayed on thedisplay section of the biomagnetic instrument of FIG. 1 upon completionof measurement;

[0050]FIG. 27 shows an averaging screen displayed on the display sectionof the biomagnetic instrument of FIG. 1;

[0051]FIG. 28 shows a single waveform screen displayed on the displaysection of the biomagnetic instrument of FIG. 1;

[0052]FIG. 29 shows a multichannel wave display screen displayed on thedisplay section of the biomagnetic instrument of FIG. 1;

[0053]FIG. 30 shows a grid map display screen displayed on the displaysection of the biomagnetic instrument of FIG. 1;

[0054]FIG. 31 shows a contour map of magnetic field screen displayed onthe display section of the biomagnetic instrument of FIG. 1;

[0055]FIG. 32 shows a map of distribution of propagation screendisplayed on the display section of the biomagnetic instrument of FIG.1;

[0056]FIG. 33 shows a time integral map screen displayed on the displaysection of the biomagnetic instrument of FIG. 1; and

[0057]FIG. 34 shows a system adjustment screen displayed on the displaysection of the biomagnetic instrument of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

[0058]FIG. 1 is a schematic block diagram indicative of a biomagneticinstrument of one embodiment of the invention. In order to eliminate anyinfluence of environmental magnetic noise, the biomagnetic instrument isinstalled in a magnetic shield room 1. A patient 2 to be tested lies ona bed 3 on his/her back for measurement thereof. A body plane of thepatient (a plane parallel to the chest-wall, in case of a chest portion)is assumed to be approximately parallel with the plane of bed 3, andthis parallel plane is assumed to be parallel with an x-y plane of anorthogonal system (x, y, z). Although an actual chest portion of thepatient is curved and slanted, it is assumed to be substantiallyparallel in order to simplify the description.

[0059] In the upper direction of the chest part of patient 2, there isdisposed a dewar 4 filled with a coolant of liquid helium (He). Thisdewar 4 accommodates superconducting quantum interference devices(SQUID) and a plurality of magnetic sensors including detection coilsconnected to this SQUID. The liquid He is supplied continuously from anautomatic He supplier 5 provided outside the magnetic shield 1.

[0060] The magnetic sensor produces a voltage which has a specificrelation with the biomagnetic field strength (or magnetic flux density)which is generated in the patient 2 and detected by the detection coils.This output voltage is input to a flux locked loop (FLL) circuit 6. Inorder to ensure for the output of SQUID to be maintained constant, thisFLL circuit 6 cancels changes in the biomagnetic fields (biomagnetism)input into SQUID by means of a feedback coil, which is referred to as amagnetic field lock. By conversion of this feedback current flowingthrough the feedback coil to a voltage, a voltage output that has aspecific relationship with the changes in biomagnetism signals can beobtained. By provision of such a detection method by means of thefeedback coil as described above, a very weak magnetic field can bedetected at a high precision.

[0061] The above-mentioned output voltage is entered into anamplifier/filter/amplifier (AFA) 7, and their outputs are sampled,subjected to A/D conversion, then entered to a computer 8.

[0062] Computer 8 is comprised of a personal computer, and numeral 8-1depicts its display unit, 8-2 depicts its keyboard, and 8-3 depicts itsmouse. The mouse is used for moving a cursor on its screen to select anobject to be processed. This operation can be executed also by operationof the keyboard. Further, an input gain 1 and an output gain 0 of AFA 7are adjustable, and AFA 7 includes: a low-pass filter (LPF) which allowsto pass a frequency signal which is lower than a first referencefrequency; a high-pass filter (HPF) which allows to pass a frequencysignal which is lower than the first reference frequency and higher thana second reference frequency; and a band elimination filter (BEF) whichcuts off the commercial power line frequency. Computer 8 can executevarious data processing, and a result of its processing can be displayedon display unit 8-1. The above-mentioned computer 8 depicted in FIG. 1shows only one embodiment of the invention, and it is not limitedthereto. There can be considered in the scope of the invention variousmodifications such as ones having a display provided with a touch panel,a coordinate indicator in place of the mouse, for example, using a trackball, joystick or the like as well. Further, a mobile computer that canbe coupled via the public telephone circuitry may be used.

[0063] For example, a direct current SQUID is used as the SQUID of theinvention. A direct bias current Ibias is applied to flow through SQUIDsuch that when an external magnetic field is applied to the SQUID, avoltage V corresponding to the applied external magnetic field isproduced. Assuming this applied external magnetic field to be expressedby magnetic flux φ, a characteristic curve of V relative to φ, i.e.,characteristic curve φ-V, is given by a periodic function. Prior tomeasurement, operation to set a DC voltage of the φ-V characteristiccurve at 0 level is carried out by adjusting the offset voltage Voff ofFLL circuit 6. Further, operation to adjust the offset voltage Aoff ofAFA 7 is carried out such that the output of AFA 7 becomes 0 when itsinput is zero.

[0064] When the external magnetic field applied to SQUID becomessubstantially great, this magnetic field tends to be trapped in theSQUID, thereby preventing normal operation from being ensured. In such acase, SQUID is heated once and returned to its normal conducting stateso as to remove the trapped magnetic field. This procedure of heatingthe SQUID will be referred to as the heat flash hereinafter.

[0065]FIG. 2 shows a layout of magnetic sensors of the invention. Thedetection coil of each magnetic sensor has two types of coils: one fordetecting tangential components of the biomagnetic field (componentssubstantially parallel to the body of the patient, i.e., x-y plane); andthe other for detecting normal components of the biomagnetic field(components perpendicular to the body plane, or x-y plane). As the coilfor detecting the tangential components of the biomagnetic field, twodifferent coils, one with its coil plane disposed in x direction and theother disposed in y direction are used. As the coil for detecting thenormal components of the biomagnetic field, a coil with its coil planedisposed in z direction is used. A plurality of magnetic sensors from20-1 to 20-8, from 21-1 to 21-8, from 22-1 to 22-8, from 23-1 to 23-8,from 24-1 to 24-8, from 25-1 to 25-8, from 26-1 to 26-8, and from 27-1to 27-8 are disposed in a matrix on a plane which is substantiallyparallel to the patient body, i.e., x-y plane. The number of themagnetic sensors may be any number. In FIG. 2, however, because thematrix is comprised of 8 rows by 8 columns, the number of magneticsensors therein is 8×8=64. Each magnetic sensor is disposed such thatits longitudinal direction becomes perpendicular (in the z direction) tothe patient body, or to the x-y plane. By way of example, although thebed surface and the x-y plane of the sensors are depicted to be parallelto each other in this embodiment of the invention, it is not limitedthereto, and they can be slanted because it is more preferable to allowfor these two planes to come into a close proximity in order to improveprecision of detection. However, since the human body of the patient isalways in motion, if the sensors are placed in direct contact with thehuman body, this motion will cause to move the detectors therebypreventing a high precision detection from being obtained.

[0066]FIG. 3 shows the structure of a sensor in each magnetic sensor foruse in detection of normal component Bz of the biomagnetic field. Thecoil of this sensor which is made of an Ni-Ti superconducting wire isdisposed such that its coil plane becomes perpendicular to thez-direction. This coil is comprised of a combination of tworeverse-wound coils 10 and 11, and its coil 10 which is closer to thepatient 2 functions as a detection coil, and the other coil 11 remotefrom the patient serves as a reference coil, which detects externalmagnetic field noise. The external magnetic field noise comes from anexternal signal source which is more remote than the patient. Therefore,this noise signal can be detected by both the detection coil 10 and thereference coil 11. On the other hand, because a biomagnetic signal fromthe patient is weak, this weak biomagnetic signal is detected only bythe detection coil 10, and the reference coil 11 is almost insensitiveto this biomagnetic signal. Therefore, because the detection coil 10 isallowed to detect both the biomagnetic signal and the external magneticnoise signal while the reference coil 11 is allowed to detect only theexternal magnetic noise signal, it becomes possible to obtain a highprecision biomagnetic field data with an improved S/N ratio by taking adifference (subtraction) between these two signals obtained by these twocoils. These coils are connected to an input coil of SQUID via asuperconducting wire of a packaged substrate on which SQUID 12 ismounted, whereby normal direction component Bz of the detectedbiomagnetic signal is transmitted to SQUID.

[0067]FIG. 4 shows arrangements of respective sensors of each magneticsensor for detecting tangential components Bx and By of the biomagneticfield. In the same drawing, the respective sensors for use in thedetection of biomagnetic field components in the tangential directionsutilize a planar coil. That is, its detection coils 10′ and 10″, and itsreference coils 11′ and 11″ are comprised of planar coils, and they aredisposed on a first and a second surfaces respectively which areseparated from each other at a given distance in the z-directions.Further, in the same manner as in the normal components' coilconnection, these coils are connected to the input coils of packagesubstrates of SQUID 12′ and SQUID 12″, respectively. A sensor 13 for usein the detection of Bx component and a sensor 14 for use in thedetection of By component are attached on two adjacent and perpendicularsurfaces of a rectangular pole, whereby a sensor capable of detecting Bxcomponent as well as By component is provided.

[0068] As for the tangential components Bx and By, they can be obtained,without using the magnetic sensors depicted in FIG. 4, through partialdifferentials of the normal component Bz with respect to x and y, whichwas obtained using the magnetic sensor of FIG. 3. In this case, usingone magnetic sensor, tangential components Bx and By as well as normalcomponent Bz can be detected for their measurement.

[0069]FIG. 5 shows a positional relationship between the magneticsensors and chest portion 30 of the patient 2 under detection.Respective dots shown in the drawing represent intersections between therows and columns in the matrix of FIG. 2, namely, respective points ofmeasurement on the patient 2, or positions of detection.

[0070] These positions of detection may be referred to as channels. Asobviously indicated in this embodiment, the direction of height of thepatient 2 coincides with y-direction, and the direction of width of thepatient coincides with x-direction.

[0071] FIGS. 6(A)-(C) show the results of biomagnetic measurement atrespective measurement positions (channels) of FIG. 5. This result ofmeasurement shows respective biomagnetic field waves changing with timeat respective corresponding channels in the matrix which were obtainedthrough the above-mentioned data processing of respective signalsdetected by respective magnetic sensors corresponding to theirmeasurement positions. The waveforms in FIG. 6 depict themagnetocardiograph waveforms of the patient because respective channelsare placed at respective positions capable of detecting biomagneticfields produced by myocardia in this embodiment of the invention. By wayof example, the waveform obtained by detection of the biomagnetic fieldsproduced by myocardial activities is referred to as the cardiomagneticwaveform. In the case where the result of measurement at each channel ofdetection is displayed in a matrix corresponding to its position asshown in FIG. 6, this display will be referred to as a grid map imaging.FIGS. 6 (A)-(C) show the cardiomagnetic waveforms obtained for a healthyperson. FIG. 6(A) depicts cardiomagnetic waveforms of tangentialcomponents Bx, FIG. 6(B) depicts that of tangential components By, andFIG. 6(C) depicts that of normal components Bz, respectively.

[0072]FIG. 7 shows cardiomagnetic waveforms of tangential component Bxobtained for a healthy person and, in particular, with respect todesignated two channels. A solid line depicts a cardiomagnetic waveformof one of these two channels and a dotted line depicts that of the otherchannel thereof. Respective waveforms in time span T1 undergoingde-polarization of the ventricle of the heart, namely, QRS waves in thecontraction period thereof are shown having respective peak times fortheir waveforms at tQ, tR and tS. Further, a time span of T wavecorresponding to the re-polarization process (expansion period) of theheart is indicated as T2. In addition to the grid map display, theresults of measurement may be displayed also by a single channel datadisplay method which displays a single channel data per each row or eachcolumn, otherwise by a multiple channel data display method whichdisplays by superimposing every channel data or a plurality of selectedchannel data. The former is referred to as the single waveform display,and the latter is referred to as the multichannel wave display.

[0073] The cardiomagnetic waveform data obtained as above are subjectedto averaging processing, contour mapping of magnetic field and that oftime integral thereof, and the results of such processing can bedisplayed. For example, in reference to FIG. 7, a predetermined time(toff) is retrospected from a time at which a raising part of QRS waveintersects a threshold line SL to a time t1, then data occurring withina time slit T3 between time t1 and time t2 are added for a predeterminedcount. This is the averaging operation, and the predetermined time slitT3 is its averaging period of time, and the predetermined time slit toffis its off-set time. The cardiomagnetic wave data may be obtained alsoby integrating it over a predetermined time span. A contour map obtainedby connecting equal points (channels) of such time integral is referredto as the contour map of time integral. Further, a contour map obtainedby connecting equal points (channels) of cardiomagnetic wave signals isreferred to as the contour map of magnetic field. Further, althoughrespective channels are set up coarsely, a pitch between contours ofmapping, namely, a difference between magnetic field strengths may bepredetermined appropriately, then by linearly interpolating betweenthese respective channels, contour mapping of magnetic field can bedrawn suitable for more precise diagnosis. As for the cardiomagneticwaves indicated in FIG. 7, a period of time from time t1 to time tRwhich coincides with the peak point of QRS wave is called as apropagation time, and a map obtained by connecting equal points of itspropagation time is called as a contour map of distribution ofpropagation time. A set level of the threshold line SL is changeable. Asfor time t1 which is determined on the basis of the time at which therising part of QRS wave intersects the threshold line SL, it may bedetermined on the basis of a time at which its falling part of QRS waveintersects the threshold line SL. Still further, the time t1 may bedetermined, by detecting time tR corresponding to a peak point of theQRS wave, and with reference to this detected time tR. A biomagneticsignal obtained according to the invention is produced by bioelectronicphenomena in the human body, and the source of its signal can beapproximated by a current dipole model. The current dipole modelapproximated as the source of its biomagnetic field is synthesized onthe contour map of magnetic field and displayed thereon, which isreferred to as a magnetic source imaging.

[0074] A series of operation including the registration of the patient,measurement on the patient registered, and its data analysis areexecuted while monitoring the panels or screens displayed on displayunit 8-1. Therefore, at first, layouts of these display panels will bedescribed prior to detailed descriptions of these series of operation.

[0075]FIG. 8 shows a basic layout of the screen (panel) displayed ondisplay unit 8-1 of FIG. 1. The upper portion of the screen is occupied,from the above sequentially, by a title bar region 801, a menu barregion 802 and a tool bar region 803 with icons. Each region describedabove may be considered to be a display region or area. This basiclayout of screen arrangements is displayed commonly on respectivedisplay screens for other objects of processing, for example, in theregistration of patients, patient data reading, biomagnetic measurement,data analysis or the like. Therefore, ease-of-use is facilitated, andmeasurement and processing times are substantially reduced.

[0076] The center area of the screen is occupied, from left to right, bypatient information section 804, analysis data section 805 fordisplaying analysis data such as graphs and waveforms, and operatingregion section 806. Further, the bottom portion of the screen isoccupied by status bar 807, which includes a message bar section 807-1which is on the left side thereof and displays a guide messagedescriptive of the next operation, and a date/time indicator 807-2 whichis located on the right side thereof. By way of example, these messagebar section 807-1 and date/time indicator 807-2 may be included in onedisplay region.

[0077] In the panel or screen of this embodiment of the invention thereare constantly displayed in the upper portion, title bar section 801descriptive of the title of its system, menu bar section 802 forexecuting basic operations of this system, and tool bar section 803which displays related operations in this menu bar section 802 theoccurrence of which is frequent for facilitating ease-of-use. Therefore,the operator is not required to search for the operation area every timethe screen is changed, and can learn a current system in operationeasily by looking at the uppermost portion of the screen. In addition,because the uppermost portion of the panel or screen is an eye-catchingportion the operator looks at initially as is the case of reading a bookor paper, provision of the basic items required for operating the systemin the uppermost portion will improve the ease of use in the mosthuman-friendly and natural way. Further, because the analysis datadisplay section 805 which is a main part of the screen is disposed inthe center portion of the screen occupying a large area thereof, itsvisibility is improved. Because the operating area section 806 specificto a current screen is disposed to the right of the main part of thescreen, the identical positional relationship between the main displayarea and the operating area which is suitable for the right-handedoperator is provided thereby facilitating smooth and natural operation.Therefore, if this screen arrangement is adopted in a screen providedwith a touch panel, the right-hand of the operator at work on itsoperation area section 806 will not disturb monitoring of its analysisdata display section 805. Still further, because the patient informationsection 804 the main function of which is for patient confirmation isdisposed to the left side of the analysis data display section 805, theoperator is ensured to be able to carry out every operations alwaysconfirming the patient. In addition, because this left side position isremotest from the right-hand side operation section, it will not disturbthe visibility of the screen even if this is adopted in the screenprovided with the touch panel.

[0078] Further, only when a patient list and its patient's data list areto be displayed, these analysis data display section 805 and operationarea section 806 are replaced by them (see FIG. 24). When a patient listscreen (FIG. 24) is displayed, patient information corresponding to apatient marked with a cursor in the patient list on display is displayedalways in the patient information section 804. Further, when analysisdata such as graphs and waveforms are displayed in the analysis datadisplay section (FIGS. 25-34), patient information corresponding to thepatient for whom the analysis data on display are obtained is alwaysdisplayed in the patient information section 804. From theseinformation, a relationship between the displayed analysis data and aparticular patient for whom the analysis data are obtained can beidentified. As described above, because the patient information section804 is always displayed at a predetermined position (left side) on thescreen of the system in the same way as the menu bar section 802, theoperator does not need to search for the patient information area everytime the screen changes, and can identify readily by looking at thepredetermined position (left side) in the screen.

[0079] In the title bar, its frame title, more specifically,“Multichannel MCG System” is displayed (FIGS. 24-34). operation elementssuch as buttons and text frames are disposed in the operation areasection 806. The menu bar section is where a desired operation menu isselected, and which menu includes “File(F)”, “Edit(E)”, “List(L)”,“measurement(Q)” (or “Data Acquisition(Q)”), “Data Analysis(A)” and“Help(H)”, and which are arranged in sequences of operation.

[0080]FIG. 9 shows contents of respective operation menus in the menusection on the screen, and these contents of menus are displayed aspull-down menus by clicking their corresponding menu buttons,respectively. Therefore, when these pull-down operation menus are notrequired, only their keywords descriptive of their respective menus aredisplayed in the menu bar section, thereby allowing for the analysisdata section and the operation area section to have a wider displayarea. When a certain operation menu is required for a certain operation,one of the above-mentioned keywords which are arranged in the sequenceof operation is selected accordingly from the menu bar section to bedisplayed for designation of its operation. Because these keywords arearranged therein from the left to the right in the order of spelling ofcharacters, natural and smooth designation of its operation can beassured.

[0081] The pull-down menu from “File(F)” includes: “Page Layout (U)”item which sets up a page layout by opening a page layout dialog frame(not shown); “Preview (V)” item for previewing prior to printing; “Print(P)” item for data printing; and “Exit(X)” to exit from the multichannelMCG system.

[0082] The pull-down menu from “Edit(E)” includes “Delete (D)” item.Measurement data of the patient in the patient list on the patient listscreen (FIG. 24) is displayed on the data list thereof, and the item“Delete(D)” is for deleting a portion of data in the data list marked bythe cursor. Thereby, the data to be deleted must be selected in advance.When this menu is clicked, a confirmation dialog frame is openedrequesting confirmation whether “Delete” is to be executed or not. When“Delete” is required, a button “OK” in the dialog frame is clicked, andwhen “Delete” is to be canceled, a button “Cancel” is clicked. Byprovision of this confirmation dialog frame operation, inadvertentoperation by the operator to delete the data will be prevented.

[0083] The pull-down menu from “List(L)” includes as its items“Registration(R)”, “List(L)”, “Delete(D)”, “Search(S)”, and“Release(X)”. When “Registration(R)” button is clicked in the pull-downmenu, a patient registration dialog frame shown in FIG. 10 is opened.This dialog frame is used for entering data items relating to thepatient. These data items that can be entered include registration date,ID number of the patient up to a predetermined count of digits, name,date of birth, height, weight, sex, disease classification information,and comments on the patient. When “Registration” button is clicked inthat dialog frame, all data having been entered are registered, andsimultaneously the input frame is cleared ready for re-entry operation,and when “Cancel” button is clicked, all the input frames are cleared,then when “Exit” button is clicked, the patient registration dialogframe is closed.

[0084] When “List(L)” is clicked in the pull-down menu, the patient listscreen (FIG. 24) is displayed. When “Delete(D)” in the pull-down menu,which is for deleting the patient in the patient list (FIG. 24) markedwith the cursor, is clicked, a confirmation dialog frame is opened priorto its deletion requesting confirmation whether its delete operation isto be executed or not, and when its deletion is required, “OK” button inthat dialog frame is clicked, and when its deletion is to be canceled,“Cancel” button therein is clicked. When any designated patient isdeleted, every data in the data list of the designated patient aredeleted simultaneously.

[0085] When “Search(S)” is clicked in the pull-down menu, a searchdialog frame indicated in FIG. 11 is displayed. After searching adesignated patient and its data, only the designated patient and itsdata having been searched are displayed on the patient list screen. Asearch target regarding the patient and data includes all the patientsand their data. Patient name, date of registration, sex, class of data,measurement date, diagnosis, comment, inspector, body position, and thelike are used as a keyword for the search of the data. A multiple facetsearch is possible based on a combination of a plurality of keywordsdescribed above. “Release(X)” in the pull-down menu is used forreleasing an exclusive display of the searched patient and its relateddata from the screen and for displaying the whole patients and the wholedata thereon.

[0086] The pull-down menu of “measurement(Q)” includes items of“Adjustment File(F)”, “Automatic Adjustment(A)”, Voff Adjustment(V)”,“Manual Adjustment(M)”, “Adjustment File(F)”, “Measurement Panel(P)”,“Sensor Diagnosis(D)”, and “AFA Offset Adjustment(O)”.

[0087] When “Adjustment File (F)” is clicked, a sub pull-down menuthereof is opened, which includes “Open (O)”, “Save (S)”, and “AlterFile Name (A)” items. “Open (O)” in the sub pull-down menu is used toopen a system adjustment screen (FIG. 34), and set up system adjustmentvalues, i.e., Ibias and Voff for the system through a designatedadjustment file which is opened. “Save (S)” is used to open theconfirmation dialog frame and to save the adjustment value in theadjustment file by overwriting the updated data over the obsolete data.“Alter File Name (A)” is used for saving the current adjustment data inanother adjustment file by altering its name.

[0088] When “Automatic Adjustment (A)” is selected in the pull-downmenu, the system adjustment screen (FIG. 34) is displayed, then biascurrent Ibias and off-set voltage Voff in FLL circuit 6 areautomatically adjusted in accordance with the flow of FIG. 22 to bedescribed later. When “Voff Adjustment (V)” is selected, the systemadjustment screen (FIG. 34) is displayed, and the off-set voltage Voffof FLL circuit 6 is automatically adjusted according to the flow of FIG.23 which will be described later. When “Manual Adjustment (M)” isselected, the manual adjustment dialog frame of FIG. 12 is opened. Usingthe scroll bar and mouse, the operator can select any channel, andmodify its bias current Ibias and off-set voltage Voff. If enteredvalues are correct and appropriate, “OK” button is clicked to set up thevalues. When “Cancel” button is clicked, the modification becomesinvalid, then this dialog frame is closed.

[0089] When “Measurement Screen (P)” is clicked, a measurement screenwhich includes a grid map (FIG. 25) is displayed. When “Sensor Diagnosis(D)” is clicked, an automatic diagnosis dialog frame as shown in FIG. 13is opened. In the sensor diagnosis or automatic waveform diagnosis step,its amplitude, its center value and its cycle of the φ-V characteristiccurve in the screen of FIG. 34 are automatically checked for theirvalidity, and any channel which is outside a designated range of themeasurement is notified to the operator as an event of an inappropriatestate unfit for the display of the φ-V characteristic curve or forupdating the status of the same curve. When any channel the state ofwhich is not suitable for measurement is detected, an error dialog frameis opened to display an error message and notify it to the operator.This unsuitable state of the channel may be notified also by displayingthe φ-V characteristic curve of that channel in a different color. Here,in the case a minimum value of the φ-V characteristic curve isautomatically checked, the unsuitable state unfit for measurement refersto a state where a difference (subtraction) between the maximum valueand the minimum value in the φ-V characteristic curve is smaller thanthe minimum amplitude detected. In the case the center value isspecified, the unsuitable state refers to a state where an absolutevalue of averages of the above-mentioned maximum values and the minimumvalues is larger than the specified center value. In the case its cycleis specified, the unsuitable state of measurement refers to a statewhere the cycle of φ in the φ-V characteristic curve is outside therange defined by the first text frame (a lower limit) and the secondtext frame (an upper limit). In order to validate automatic diagnoses ofthe minimum value of amplitude, the center value and the cycle,respective check frames on the left side of respective items may bechecked using the mouse to indicate “x” mark therein, then a desiredvalue may be entered through the text frame corresponding thereto.Automatic diagnosis parameters entered as above become effective uponclicking “OK” button, and this dialog frame is closed. When “Cancel”button is clicked, the entered parameters become invalid, and the dialogframe is closed. “AFA Offset Adjustment (O)” is used when adjustingoff-set voltage Aoff of AFA 7, and when “AFA Offset Adjustment (O)” isclicked, a measurement screen (FIG. 25) which belongs to the single wavedisplay is displayed.

[0090] The pull-down menu of “Data Analysis (AQ)” includes “Averaging(A)”, “Single Channel Wave Display (W)”, “Multichannel Wave Display(M)”, “Grid map Display (G)”, “Mapping of Magnetic Field (B)”, “Mappingof Time Integral (T)”, “Mapping of Distribution of Propagation (P)”,“Magnetic Source Imaging (S)”, “Line Mode (L)”, and “Fill-in Mode (F)”.

[0091] When “Averaging(A)” is clicked, an averaging screen (FIG. 27) isshown, when “Single Wave Display (W)” is clicked, a single waveformscreen (FIG. 28) is shown, when “Multichannel Waveform display (M)” isclicked, a multichannel waveform screen (FIG. 29) is shown, and when“Grid map display (G)” is clicked, a grid map screen (FIG. 30) is shown,respectively, then a check mark (x) indicative of its selection is shownon the left side of its menu. Further, when “Mapping of flux (B)” isclicked, a map of magnetic field screen (FIG. 31) is shown, when“Mapping of time integral (T)” is clicked, a map of time integral screen(FIG. 32) is shown, and when “Mapping of distribution of propagation(P)” is clicked, a map of distribution of propagation (FIG. 33) isshown, respectively, and a check mark (x) indicative of its selection isshown on the left side of its menu. Still further, when “Magnetic sourceimaging (S)” is clicked, an inverted triangle mark is indicated on theleft side of its menu, and a magnetic source approximated by a currentdipole is superimposed on the map of magnetic field (not shown). As forthe mapping of magnetic field, mapping of time integral, mapping ofdistribution of propagation, and magnetic source imaging, when “Linemode (L)” is selected, respective lines on their screens are displayedwith their gaps between lines not painted or filled in, and when“Fill-in mode (F)” is selected, their screens are displayed with thegaps between respective lines filled in. In order to indicate acurrent-state mode selected, a check mark indicative of its selection isshown on the left side of its menu.

[0092] The pull-down menu of “Help (H)” includes “Contents (C)”, “Searchby Keywords (S)”, and “Version Information (A)”, which are used forindicating the contents, searching a topic by way of a keyword, andopening a version dialog screen, respectively.

[0093] In the tool bar 803, there are disposed icons for “PatientRegistration” (808), “Patient List” (809), “Print” (810), “Preview”(811), “System Adjustment” (812), “Measure” (813), and “Data Analysis”(814). These icons are linked with menu functions, and these iconsdesignated can be chosen from their pull-down menu items according totheir frequencies of use although the illustration of which is omitted.Namely, “Patient Registration” (808) corresponds to “Registration (R)”of “List (L)”; “Patient List” (809) corresponds to “List(L)” of “List(L)”; “Print” (810) to “Print (P)” of “File (F)”; “Preview” (811) to“Preview (V)” of “File (F)”; “System Adjustment” ((12) to “Manualadjustment (M)” of “Measurement(Q)”; “Measure” (813) to “MeasurementPanel (P)” of “Measurement(Q)”; and “Data Analysis” (814) to “Grid mapdisplay (G)” of “Data analysis (A)”, respectively. As for the menu whichis linked with its icon, this menu can be opened directly by clickingits icon. Any operation the frequency of its use is high, and which isprovided with an icon displayed abutting to the analysis data screen,can be accessed easily by clicking its icon, therefore, its operationthrough its icon which is more easy to recognize and handle than throughthe operation of the above-mentioned menu bar can facilitate itsoperation. Further, the above-mentioned icons can be selected fordisplay at discretion by the operator, or may be automatically displayedon the tool bar section 803 in accordance with the frequency of its use.

[0094] Now, with reference to FIGS. 14-34, a series of operationsincluding the system adjustment, the registration of patients,measurement on the patients registered, to the data analysis of thusobtained data, will be described in the following.

[0095]FIG. 16 shows a schematic flowchart of operations according to theinvention. When the power of computer 8 is turned on (step S-1), theoperating system is set up, and a program start icon is displayed ondisplay unit 8-1 (S-2). When a multichannel MCG system program icon isselected in step S-3, the patient list screen indicated in FIG. 24 isdisplayed (S-4).

[0096] In the system according to this embodiment of the invention, asan initial screen at the time of system setup, the patient list screenof FIG. 24 is displayed. This is because that the management in thissystem is executed via the patient information as its keyword since arelationship linking between a particular patient and his/her detecteddata or analysis data is considered very important. That is, becausemanagement of the detected data and analysis data cannot be executedwithout the patient information. Thereby, in this system, a patient isregistered at first through the patient list screen, or when the patientis already registered, the patient is designated on that screen, thenthe step advances to the measurement step in the case of data updating,alternatively when there exist data having been detected, a target datais specified thereon. By way of example, a set-up wait time screenindicating a wait time required for the system set-up may be displayedprior to display of the patient list screen, or a screen to display thecontents of the system may be provided as well.

[0097] In the patient list screen of FIG. 24, the left side thereof isoccupied by the patient information area, and in the upper portion ofthe right side area thereof is displayed a patient list, and in thebottom portion of the right side area thereof is displayed a data list.Respective items displayed in the patient information area on the leftside are the same as described with reference to FIG. 10. Items in thepatient list in the upper portion include ID (patient's ID number),name, date of registration (date of data entry), measurement counts (thenumber of measurement executed), date of birth, age, height, weight,comments (regarding the patient) and so on. The patient list can bescrolled up and down with a vertical scroll bar, and the items of thepatient list can be scrolled horizontally with a horizontal scroll bar.A selected row of a patient is displayed in an emphasized mode.

[0098] Items in the data list on the patient designated include ID, typeof data (raw data or averaged), sampling interval (sampling interval ofsignals in ms during measurement), sampling time (s), classification(disease classification information), date and time of measurement,comments on data, and the like. The data list can be scrolled up anddown with a vertical scroll bar, and the items of the data list can bescrolled horizontally by a horizontal scroll bar. A row of data selectedis displayed in emphasized mode.

[0099] According to this patient list screen, a row of information foreach patient is displayed in the patient list. Thereby, information ofeach patient can be clearly distinguished from that of other patientsarranged vertically thereby improving discrimination therebetween, andthereby preventing inadvertent operation such as to select a wrongpatient. This information on each patient can be scrolled horizontallyby the horizontal scroll bar, and information on the designated patientcan be displayed item by item vertically in the patient information areawithout limiting its visibility. The visibility may be further improvedby arranging such that the items in the data list on each patient can bescrolled vertically or horizontally. Further, by displaying informationfor each patient in a row, a many number of patients can be monitored atonce, thereby reducing the frequency of scrolling using the verticalscroll bar. Still further, by a simple operation to click the cursorwhich is moved to a target patient on the patient list, the data on thetarget patient can be displayed readily in the data list area in thebottom portion. Moreover, because the patient list and the data listareas are disposed in vertical directions such as to minimize eyemovements, their relevance can be recognized easily. Still further,because size of the data list area can be changed easily through asimple operation of the cursor, i.e., by moving the cursor to the upperedge of the data list area and dragging upward the same, the size of itsarea can be increased in accordance with the number of list items in thedata list.

[0100] In step S-5, a desired patient's row is selected from the patientlist on the patient list screen. In the case of averaging process whichwill be described later, a raw data line is selected always. In the nextstep S-6, the flow can be branched to four sub-menus by menu selection.One of which is to select a submenu “End of magnetocardiograph (X)” fromthe menu “File (F)”. Upon selection of this sub-menu, final processingto close the screen is executed (S-7), and thereby shutting down thesystem (S-8). Then, the power of computer 18 is turned off (S-9) tocompete the flow.

[0101] According to the other sub-menus, averaging process (S-10), dataanalysis (S-11), and measurement (S-12) are executed. The averagingprocess is enabled through selection of a sub-menu “Averaging (A)” inthe menu “Data Analysis (A)”. Further, the data analysis is enabled byselecting any one of the submenus of “Single Wave Display (W)”,“Multichannel Wave Display (M)”, “Grid Map Display (G)”, “ContourMapping of Magnetic Flux (B)”, “Contour Mapping of Time Integral (T)”,“Contour Mapping of Distribution of Propagation (P)” and “MagneticSource Imaging (S)” in the menu of “Data Analysis (A)”. Further, themeasurement is enabled by selecting the submenu “Measurement Panel (P)”in the menu “measurement (Q)”. After completion of steps S-10, S-11 andS-12, the flow returns to step S-4. Regarding the selection of a patientin step S-5, the averaging process in step S-10, the data analysis instep S-11, and the measurement in step S-12, their detailed descriptionswill be made with reference to FIGS. 17-20 in the following.

[0102]FIG. 17 shows the flow of the patient selection in step S-5 inFIG. 16. In this case of the patient selection, its flow is branchedinto four sub-menus by menu selection or by patient selection. One ofthem is to select step S-5-1 and specify a patient whereby completingthe patient selection flow. According to another branch sub-menu, thesub-menu “Search (S)” in the menu “List (L)” is selected. Thereby, thesearch dialog frame shown in FIG. 11 is opened (S-5-2), and through thisdialog frame, patient search conditions are entered (S-5-3). Thereby,the target patient is searched (S-5-4), and accordingly the contents ofthe patient list displayed on the patient list screen shown in FIG. 24are updated (S-5-5). According to still another branch sub-menu, thesub-menu “Release (X)” is selected in the menu “List (L)”. In this case,the selected patient is released to return to the whole patient list(S-5-6), the contents of display for the patient list are changed(S-5-5). According to the remaining branch sub-menu, the sub-menu“Registration (R)” is selected in the menu “List (L)”. In this case, thepatient registration dialog frame shown in FIG. 10 is opened (S-5-7),and through which patient information is entered (S-5-8). As to thesesteps, judgment of completion of data entry is executed for everypatients until all data are entered (S-5-9), and upon completionthereof, updating of the patient list is executed (S-5-5).

[0103] According to this embodiment of the invention, except for thename and address of the patient or the like which are to be entered incharacters, a plurality of input data or operation instructions to beentered are displayed selectively on the screen or may be displayedthereon by means of the pull-down menus, thereby allowing inputoperation of a selected object to be readily entered by designating thesame using the mouse. Thereby, because almost every manual data entryoperations required for this system can be executed using the mouse, itcan offer a user-friendly environment, easy-to-operate even by such anoperator who is not accustomed to keyboard operation, and reduce thetime required for data entry and operation as well. Further, because theplurality of objects or targets for selection in the pull-down menus arepreset in advance in the system or provided in the state allowable fortheir entry or operably, and are readily displayed, inadvertent input oroperation can be prevented. Still further, in this embodiment of theinvention, because it is allowed for the operator to enter additionaldata on the input area at a place designated by the cursor and throughthe keyboard operation, flexibility of data input is ensured for theoperator. Although character input by means of the keyboard operation iscontemplated in this embodiment of the invention, it is not limitedthereto, and a dialog of the keyboard for data input may be displayed onthe screen to be operated by the mouse, further a hand-written inputdialog may be displayed to be operated by the mouse, or the screen maybe provided with a touch-panel input device through which data can beinput manually by hand or an input pen. By provision of sucharrangements, the ease-of-operation in data input can be improvedsubstantially.

[0104]FIG. 18 shows a flow of measurement in step S-12 in FIG. 16. Atfirst, a grid map of cardiomagnetic waves of FIG. 25 is shown as itsinitial panel or screen (S-12-1). In the operation area section of FIG.25, it is allowed to execute respective operations of channel selection,ON-OFF of the waveform monitor, lock/unlock of FLL circuit 6, automaticadjustment of offset voltage of AFA7, and heat flashing. It is alsopossible to set up signal sampling conditions, waveform display scale,and AFA parameters.

[0105] Its channel matrix includes 8×8=64 channels. All these channelscan be selected by clicking “All Channel Select” button, or by draggingthe cursor diagonally across the channel matrix. Alternatively, thesechannels can be selected according to a row or a column in the channelmatrix, or per channel item thereof by dragging any one of them. Ineither case, a cardiomagnetic wave corresponding to any one of thechannel items selected is displayed on the analysis data display area.In the case of channel selection by a row or column, they are displayedas shown in FIG. 26. In this case, designated waves are displayed infull scale at least on the time axis. Namely, in the case where all ofthe 64 channels are dragged, the analysis data display area is dividedinto a mesh so as to allow for all the channels to be displayedsimultaneously as shown in FIG. 25, while in the case of channelselection per row or column, the analysis data display area is dividedvertically into line sections each having a full scale time axis asshown in FIG. 26, thereby allowing their waveforms displayed in afamiliar graph mode easy to recognize.

[0106] As for monitoring of these waveforms, when “ON” button ispressed, signals are read at a predetermined interval of time, forexample, from 0.5 sec. to 2 sec., and updating of these waveforms isrepeated in order to monitor the cardiomagnetic signals of the patient.When “OFF” button is pressed, updating of the waveforms is interrupted.Regarding the FLL, when “Lock” button or “Unlock” button is clicked,magnetic lock or its lock release can be executed for all 64 SQUIDsensors. In this case, when either one of these buttons is pressed, itsstate is maintained until the other one of these buttons is pressed,thereby preventing inadvertent occurrence of a state which is notselected.

[0107] Further, when “AFA Offset Adjustment” button is clicked, itsoff-set voltage is automatically adjusted. Further, when “Heat Flash”button is clicked, the heat flash operation dialog frame indicated inFIG. 14 is opened. By selecting a channel with the mouse or an arrowkey, and clicking “OK” button, a heat flash operation of the SQUID ofthe selected channel can be executed. By clicking “Cancel” button, thedialog frame is closed completing its process.

[0108] As for the time (measurement time) and its interval, a desirablevalue can be selected from selective values in the pull-down menu whichcan be opened by clicking its corresponding text frame having aninverted triangle mark.

[0109] These selective values for the time are, for example, 1 s, 5 s,10 s, 30 s, 1 m, and 2 m, further as to the interval they are, forexample, 0.1 ms, 0.5 ms, 1.0 ms, 2.0 ms, 4.0 ms, 5.0 ms and 10.0 ms.This time also may be set selectively between approximately 1 sec and 24hours when required. “Time” in “Scale” frame indicates a time scale inmsec., i.e., horizontal scale, and “Signal” therein indicates anamplitude scale of signals after A/D conversion, i.e., vertical scale.These values also can be selected from selective values in a pull-downmenu which is opened by clicking a corresponding text frame in the sameway as in the case of the sampling time and interval setting.

[0110] The AFA parameter frame includes input gain Igain, output gainOgain, frequency of low-pass filter (LPF), central frequency of bandelimination filter (BEF), and cutoff frequency of high-pass filter. Inthe same manner, these values can be selected as desired from selectivevalues or characters in their pull-down menus which can be opened byclicking corresponding text frames. As for input gain Igain, its valuecan be selected, for example, at 1, 2, 5, 10, 20, 50, 100, 200, 500 and1000; as for output gain Ogain, it can be selected, for example, at 1,10 and 100; as for the LPF, it can be selected, for example, at 30, 50,80, 100, 200, 400 Hz and 1 kHz; as for the BEF, it can be selected, forexample, at Off, 50 Hz and 60 Hz; and as for the HPF, it can beselected, for example, at 0.05 Hz, 0.1 Hz and through. By way ofexample, these values may be entered directly through the keyboardinstead of the above-mentioned selection via their screens.

[0111] Further, in addition to the main 64 channels, auxiliary channels,for example, of 16 channels may be provided so that these auxiliarychannels display, for example, electrocardiograms. In the bottom portionof FIG. 25, there is displayed a waveform at the tenth channel as areference channel. This waveform is an electrocardiogram obtained at thetenth channel of the auxiliary channels. Generally speaking, thecardiomagnetic wave includes a magnetic noise while theelectrocardiogram does not includes such a noise. Therefore, throughcomparison of a cardiomagnetic wave with an electrocardiogram displayedin the reference channel, information regarding whether or not amagnetic noise is included in the cardiomagnetic wave can be obtained.Of course, this electrocardiogram may be obtained not from the auxiliarychannels but from any of the normal 64 channels. Further, instead ofthis electrocardiogram wave, a brain wave, blood stream wave, bloodpressure wave or the like may be used. Still further, it may be arrangedsuch that an electrocardiogram wave of a pregnant woman is compared witha cardiomagnetic wave of a fetus. Further, the reference waveform is notlimited to that of one channel, and a plurality of reference waveformsof a plurality of channels may be displayed. Still more, the referencechannels displayed here are not limited to the signals from the patient,but various other signals from control devices may be displayed for thepurpose of inspection and maintenance as well.

[0112] Again, with reference to the flow of FIG. 18, when the monitorchannel is selected in step S-12-2 in the same manner as described, andFLL's lock button is clicked, magnetic field lock of all the SQUIDs isexecuted in step S-12-3. In this condition, measurement parametersincluding sampling timing and signal setting, and AFA parameters are setup (S-12-4). This set-up process can be omitted in the subsequent eventprovided that the same parameter set-up conditions can be used, therebyminimizing the parameter set-up time in the subsequent event. Further,this parameter set-up conditions may be stored attached with titles easyto access.

[0113] When “Start” button in “Measurement” frame is clicked,measurement operation is started, and “measurement in Progress” screenof FIG. 15 is displayed together with a progress bar indicative of thestate of progress of its operation (S-12-5). The progress bar in thisembodiment of the invention is indicated as a bar graph which extendsfrom the left to the right in the direction of its progress, however, itis not limited thereto, and it may be indicated as a circle or the likefor indicating the degree of processing or time. Further, this progressbar is preferably displayed at a predetermined marginal position on themeasurement screen such that its display does not disturb the display ofthe measurement screen so as to minimize any inadvertent operation.

[0114] When the measurement operation starts, signal waves on displayare fixed as they are, and the progress bar is indicated on the fixedscreen. Updating of the progress bar is repeated, for example, everysecond until its set time is up (S-12-6). When “Stop” button in“Measurement” frame is clicked, the measurement operation is stopped.When the measurement is complete, the screen of FIG. 26 is displayed forconfirmation of their waveforms (S-12-7). Then, it is determined whetheror not to save the data (S12-8).

[0115] When the data needs to be saved, menus of “File (F)”-“Save (S)”are selected, then its signal is saved, and added to the data list ofthe patient concerned (S-129). Then, it is determined whether or not themeasurement operation is necessary once again including the case wherethe save operation is not required (S-12-10), if necessary, theabove-mentioned steps are repeated, and if not, the whole steps of themeasurement are completed. In this instance, menu selection so as toreturn to the screen of FIG. 24 is executed. By way of description, FIG.26 indicates an example where channels of rows at the second column areselected.

[0116] In FIG. 26, a scroll bar 262 having a scroll frame which ismovable is disposed in the bottom portion of the analysis data displayarea. Scroll frame 261 which is movable horizontally between the bothends of scroll bar 262 has a width w which represents a time scale. Atime width between the both ends of the scroll bar 262 represents ameasurement time. Therefore, a waveform displayed is an enlargedwaveform of a part of the wave generated during a designated measurementtime slit, said part of the waveform corresponding to the time scale wof scroll frame 261. Thereby, the operator is allowed to learn at aglance the time scale (the width of scroll frame 261) of a waveformcurrently displayed in part on the analysis data screen in particularwith respect to the measurement time (the width of scroll bar 262), andfurther whether its waveform belongs to the former half or the latterhalf portions of the measurement time slit, thereby capable of improvingtheir visibility for recognition substantially. Still further, becausethe position of the scroll frame 261 and the waveform in display on theanalysis data screen area are linked, it may be arranged such that thedisplay region of the analysis data display area is moved by draggingthe cursor positioned at the scroll frame 261 so as to allow for thewaveform at the desired time to be displayed thereon. By sucharrangements, the scroll bar 262 can be used for reviewing the contentsand accessing to their detailed data as well as for confirmation oftheir waveforms at any specified time.

[0117]FIG. 19 shows a flowchart of the averaging process in step S-10 ofFIG. 16. In the averaging process, in order to eliminate a noise in eachdata detected at each channel, data at each channel are added and anaverage thereof is computed. In order to set the base time for executingan averaging process for each channel, the following steps of processingare performed, then the averaging process of each channel is executed.

[0118] First of all, raw data of the designated patient is read in stepS-10-1. This step is executed by clicking a line the “Data Type” ofwhich is indicated as raw data in the list data in FIG. 24. Thereby,cardiomagnetic waves of respective channels in a first column aredisplayed as the initial display as shown in FIG. 27 (S-10-2). Then, adisplay channel is selected (S-10-3). By way of example, FIG. 27 shows acase where the second column channels are selected. Then, a set-upchannel is specified (S-10-4). This step is executed by clicking“Channel” text frame in the “Averaging” frame provided in the operationregion, or by clicking a particular area where the waveform of a desiredchannel is displayed using the mouse. In this case, when a trianglebutton in the text frame is clicked, the channel number increases, andwhen an inverted triangle button therein is clicked, the channel numberdecreases. FIG. 27 shows the case where its specified channel is at thesecond column and the second row. By this channel designation, aparticular channel serving as the base time for its averaging process isdesignated. For this particular channel, a most typical channel or thathaving a waveform easy-to-see is preferably selected. If no appropriatechannel having an appropriate waveform is available in the selected rowor column, the flow can be returned to step S-10-3 to repeat the stepstherefrom.

[0119] Further, when any one particular channel is designated on theanalysis data display area, threshold cursor 271 is displayed indicativeof the position of the designated channel as shown in FIG. 27. Thereby,the designated channel can be recognized visually for its confirmation.In FIG. 27, three slider cursors 273-275 are shown in the upper portionof the analysis data display area 805, which are automatically displayedat the same time when the screen of FIG. 27 is displayed.

[0120] In step S-10-5, a threshold value, off-set time and averagingtime which are the averaging conditions are set up by clicking theircorresponding text framees in the “Averaging” frame. Their digit numberincreases when the triangle button is clicked, and decreases when theinverted triangle button is clicked. Set-up of a threshold value is doneby selecting an appropriate number indicative of its threshold in“Threshold” text frame. By this selection, threshold cursor 271 isautomatically moved to the position corresponding to this digit numberselected. This position of movement can be clearly confirmed on itscursor line. Because any change (selection) in the digit numberindicative of its threshold in the “Threshold” text frame and themovement of the threshold cursor 271 are linked each other, itsthreshold can be set up also by moving the threshold cursor 271. Slidercursor 273 indicates a point of time (base time point) at which the riseportion of a wave coincides with the threshold which is set up by thethreshold slider cursor 271, and this indicated position of coincidencecan be clearly confirmed by its cursor line. The slider cursor 273follows the movement of the base time point which changes its positionwith the changes of the threshold. Upon selections of digit numbersindicative of an off-set time in the “Off-set” text frame, and of anaveraging time in the “Time” text frame, slider cursors 274 and 275 aremoved to positions corresponding to selected numbers, respectively.Their positions of movement can be clearly confirmed visually by theircursor lines. The movement of slider cursors 274 and 275 is linked withthe selection of numbers in the “Off-set” text frame and the “Time” textframe. Therefore, setting of the off-set time and averaging time isenabled also by the movement of the slider cursors.

[0121] In step S-10-6, it is set up for the averaging whether to beexecuted in an automatic mode or in a manual mode (S-10-7). Then, when“Set-up OK” button is clicked in step S-10-8, add operation is executed.When “Cancel” button is clicked, all of the averaging conditions arecanceled. As for addition, a time (t: base time) is searched for achannel at which its wave exceeds a set-up threshold (S-10-9), then itswaveform is displayed with time (t) in the center thereof, that is, thewaveform in a time slit between t-50 msec and t+50 msec is displayedwith time (t) positioned at the center of the display (S10-10), then itis judged whether the manual mode cancel is selected or not (S-10-11),if not, addition of its waveforms is executed (S-10-12). Steps fromS-10-9 to S10-12 are repeated as many as the counts of add operation foreach channel, and the added data are divided by the counts of addition(S-10-13), then the averaging process is completed.

[0122] As described above, on the screen of the averaging process shownin FIG. 27, various conditions for the averaging process can be inputand operated both from the operation region and the analysis datadisplay area 805. Therefore, it can be arranged such that, for example,general conditions are set up roughly on the analysis data display area,and details thereof are set up in the operation region, therebyproviding versatile set-up methods to the operator, and minimizing thetime required for setting such conditions. Especially, in thisembodiment of the invention, any particular channel which is to serve asthe reference in the averaging process can be selected from a pluralityof channels displayed on the analysis data display area 805 bydesignating the most appropriate one of them using the cursor, therebyminimizing inadvertent operation and improving the ease-of-operation. Inaddition, because the threshold cursor and the slider cursors aredisplayed in the vicinity of the designated channel, visual recognitionis facilitated. Still further, because by means of these thresholdcursor and the slider cursors disposed in the vicinity of the designatedchannel, the entry and/or operation of various conditions for theaveraging process can be executed, the eye-movement of the operator isreduced substantially, and the layout of the screen can be set upsuitable for visual recognition of the waveforms displayed, therebyminimizing inadvertent operation and improving the operativeness.Furthermore, for the economy of the operation, it may be arranged suchthat these set-up conditions which are updated are saved to be displayedas the subsequent set-up conditions, or stored in memory with a titleattached.

[0123]FIG. 20 shows a flow of the data analysis in step S-11 of FIG. 16.This data analysis is intended for obtaining information necessary fordiagnosis from various waveforms and charts which are displayed. By menuselection in FIG. 9, screens indicative of various types of waveformsand charts can be selectively displayed. Namely, by selecting “Singlewave (W)” in “Data Analysis (A)”, the single waveform screen of FIG. 28is displayed (S-11-2); by selecting “Multichannel Waveform (M)” in “DataAnalysis (A)”, the multichannel waveform screen of FIG. 29 is displayed(S-11-3); by selecting “Grid Map Display (G)” in “Data Analysis (A)”,the grid map wave screen of FIG. 30 is displayed (S-11-4); by selecting“Mapping of Magnetic Field (B)” in “Data Analysis (A)”, the mapping ofmagnetic field screen of FIG. 31 is displayed (S-11-5); by selecting“Propagation Time Mapping (P)” in “Data Analysis (A)”, the mapping ofdistribution of propagation screen of FIG. 32 is displayed (S-11-&); andby selecting “Time Integral Mapping(T)” in “Data Analysis (A)”, themapping of time integral screen of FIG. 33 is displayed (S-11-7),respectively. Then, by selecting “Exit the Magnetocardiogram (X)” in“Data Analysis (A)”, the system ends.

[0124] By clicking a radio button (a circle button) in the operationregion, a waveform or chart screen designated by this click operation isdisplayed alternatively. That is why, in FIG. 20, the branch frame isnot tagged with “Branch by Menu”, but is tagged with “Branch by Menu orRadio Button”. Therefore, according to this embodiment of the invention,various analysis data can be obtained without executing the selection ofmenus in FIG. 9, but simply clicking the radio button in the operationregion, thereby minimizing the operation time and inadvertent operation,as well as improving the operativeness of the system.

[0125] A magnetic field strength (magnetic flux density) in “Scale”frame in FIGS. 28-30 indicates a full scale value in unit of pT on theplus side or the minus side relative to a zero level of reference. Thisfull scale value can be selected in its pull-down menu which is openedby clicking a triangle button in its text frame. By clicking a radioframe in “Display Component” frame in FIGS. 28-33, waveforms of a normalcomponent or tangential component can be displayed selectively.

[0126] In FIG. 28, waveforms of respective channels selected by thechannel selection operation are displayed with their offset timeadjusted at the left end of the analysis data region. According to thisanalysis data displayed on the screen, because respective waves ofrespective channels are arranged vertically, their waveforms andamplitudes of respective channels can be compared easily. In FIG. 29,the respective waveforms arranged vertically in FIG. 28 are displayed ina superimposed multichannel mode thereby allowing comparison ofwaveforms and their amplitudes at a glance. Further, in FIG. 30, everychannel waveforms are displayed on the screen with the off-set time asthe base thereof in the same manner as in FIGS. 28 and 29. Therefore,the operator can select any number of channels which is appropriatetherefrom as required for the data analysis.

[0127] With reference to FIG. 31, a long rectangular frame 310 isarranged vertically to the right side of the analysis data region as amagnetic field strength index frame. This index frame is partitionedinto 12 sections painted with different colors or gradations differentfrom each other. This is contemplated for improving visualperceptibility by painting magnetic field strengths in respective islandpatterns obtained by contour mapping of magnetic field according to theinvention. Namely, assuming that a center position 311 in the center inthe vertical direction of the index frame 310 has a magnetic fieldstrength of zero, and that the upper six sections above the centerposition 311 is defined as a first to sixth sections sequentially fromthe below thereof, then it may be arranged such that the first sectioncovers a magnetic field strength range from 0 to 2 pT; the secondsection covers from 2 to 4 pT; the third section covers from 4 to 6 pT;the fourth section covers from 6 to 8 pT; the fifth section covers from8 to 10 pT; and the sixth section covers from 10 to 12 pT, respectively.As for the other six sections below the center portion, they may bearranged in the same manner as above. However, the upper sections abovethe center position indicate plus magnetic field strengthes in thepositive direction, while the bottom sections below the center positionindicate minus magnetic field strengthes in the negative direction.Respective charts of magnetic field mapping of FIG. 31 are displayed ina different color or with a different gradation according to theirrespective magnetic field strengthes as defined by respective magneticfield strength index sections and their corresponding colors orgradation. By way of example, warm colors may be assigned to the plusmagnetic field strengthes, while assigning cold colors to the minusmagnetic field strengthes, and assigning yellow color to the centersection. Thereby, respective magnetic field strengthes can be recognizedby a difference in colors or its gradation, thereby improving visualperceptibility. In addition, according to this embodiment of theinvention, because the index frame 310 is provided in the vicinity ofthe analysis data display area, respective color objects for comparison,that is, painted colors on the map and preset colors in the index frame310, can be compared easily for confirmation with a least eye movement,thereby allowing for a precise correspondence to be judged betweenrespective levels of magnetic field strengthes in the index frame andactual colors of the mapping. By way of example, in the embodiment ofthe invention, the index frame 310 is disposed on the right side of theanalysis data display area, however, it not limited thereto, and thesame may be arranged anywhere in the vicinity of the analysis datadisplay area, for example, in the upper portion, in the bottom portionor on the left side thereof.

[0128] Further, in FIG. 31, a “Map Number” in “Reconstruction Parameter”frame indicates the number of the magnetic field maps to be displayed, a“Maximum Value” therein indicates the magnetic field strength on eitherend of the index frame 310, and a “Pitch” therein indicates an magneticfield strength range corresponding to a length of each section in theindex frame 310. These values can be selected by clicking its trianglebutton or inverted triangle button in each corresponding text frame.

[0129] In the bottom portion of the analysis data display area, thereare displayed an electrocardiac waveform of the reference channel, andtwo cursors 311 and 312 for specifying mapping time. Between these twocursors 311 and 312 for map time specification, there are displayed aplurality of divisional lines with a same pitch. The number of theplurality of division lines is identical with the number of the mapsselected by the map number selection operation. Respective positions ofthe two cursors for mapping time specification are movable independentlyin horizontal directions. When the distance between the two cursors ischanged with the movement of these cursors, pitches of the divisionallines change accordingly, with their pitch distance, however, maintainedequal between respective lines. It is, however, not limited thereto, andeach divisional line may be provided with a cursor so as to allow forits pitch to be set independently. The number of the contour maps ofmagnetic field displayed in FIG. 31 is 16, and these contour maps arethose obtained at a particular period of time designated by the positionof the division lines on the electrocardiac waveform, and each contourmap is displayed with its mapping time to show when it is drawn.

[0130] Thereby, in the same way as described with reference to FIG. 26,the operator can learn at a glance a particular contour map currentlybeing displayed on the analysis data display area coincides with whichrange (a width between the two cursors) in the analysis time (a width ofits electrocardiac waveform), and the range indicated by the contour mapcoincides with which area in the analysis time, thereby substantiallyimproving visual perceptibility. Further, the range of the contour mapcan be moved and set easily by movement of these two cursors using themouse. Still further, by allowing the pitch between respective divisionlines to be set freely, an indefinite portion can be divided densely formore precise analysis while the other portions divided sparsely, therebyoffering versatile analysis environments to the operator.

[0131] Further, when a “Current Direction” check frame in the operatingarea is clicked to indicate an arrow mark therein, an arrow mark isdisplayed on the contour map of magnetic field. This contour map withthe arrow mark displayed is referred to as the arrow map (not shown). Asfor this arrow mark, its position indicates the position of its channel(position of the magnetic sensor), its length indicates the strength ofits magnetic field, and its direction indicates the direction of acurrent converted from that of its magnetic field, respectively.

[0132]FIG. 32 shows a contour map of propagation time. In this figure, astart position of propagation time (time t1 in FIG. 7) can be changed bymoving the position of cursor 321 movable on the waveform of thereference channel, and this change in the position of cursor 321 can beenabled by dragging the cursor using the mouse.

[0133] With reference to FIG. 33, there are displayed two time integralmaps and a subtraction map. This “Subtraction” in the time integralmapping can be displayed readily by clicking its check frame to show acheck mark. When the “Subtraction” is checked, four cursors 331-334appear on the reference wave, and further two time integral contour mapsare displayed side by side in the upper portion of the display area, anda contour map of subtraction is displayed in the bottom portion of thedisplay area, respectively. These two time integral maps are obtainedfrom values of cardiomagnetic waves which are time integrated in timeslits of 100 ms to 140 ms and 180 ms to 240 ms, respectively, which areset using cursors 331 and 332, and 333 and 334 on the reference wave.These time slits can be changed by dragging cursors 331 and 332 as wellas cursors 333 and 334 using the mouse. The subtraction map indicates adifference between these two time integral maps. When no check markappears, as for the cursors, only two cursors, for example, 331 and 332are displayed, and as for the time integral mapping, only one timeintegral map is displayed. Of course, the integral time can be changedby changing the positions of the cursors. As described above, accordingto the embodiment of the invention, by clicking the check mark in the“Subtraction display”, two sets of cursors are displayed for promptingthe subsequent operation. Therefore, without causing any ambiguity inoperation, its operating time can be reduced substantially, and itsoperability can be increased because the range of its time slits can bereadily set by dragging the two sets of cursors using the mouse.

[0134]FIG. 21 shows the flowchart of the system adjustment according tothe invention. The flow is branched to five steps by menu selection instep S-15. In this case, some data currently on display is saved as theyare (S-13), and the φ-V characteristic curve of FIG. 34 is displayed(S14). In the case where “Full Automatic Adjustment (A)” in “Measurement(Q)” is selected, adjustment values of Ibias and Voff for the allchannels are automatically computed (S-16), the automatic computation ofwhich will be described later, and the computed adjustment values areset up in the FLL circuit (S-17), then the flow returns to step S-14.

[0135] In the case where “Voff Adjust (V)” of “Measurement(Q)” isselected, a value of Voff is computed for the designated channel (S-18),the computation of Voff will be described later, then the flow advancesto step S17 which is already described. In the case where “ManualAdjust. (M)” of “Measurement(Q)” is selected, the manual adjustmentdialog frame as indicated in FIG. 12 is opened (S-19). When the operatorinputs adjustment values of Ibias and Voff for each channel, these inputvalues are accepted (S-20), and they are set in the FLL circuit byclicking “OK” button in the dialog frame(S-21). Then, the dialog frameis closed (S-22), and the flow advances to step S-17.

[0136] When the “Adjustment File (F)” of “DACQ(Q)” is selected, the flowis further branched into two substeps by its sub pull-down menu (S-22).Namely, when selection of “Open (0)” in the sub pull-down menu, theoperator is asked for its file name, and the operator inputs its filename including the contents of FIG. 11 (S-23). The contents of itsadjustment value file are set in the FLL circuit (S-24). Further, byselection either of “Measurement(Q)”-“Adjustment Value File (F)”-“Save”and “Alter File Name (A)”, the same operation as in step S-23 can beexecuted (S-25), thereby allowing its adjustment values to be written inthe adjustment value file (S-26).

[0137]FIG. 22 shows the flow of the automatic computation in step S-15in FIG. 21, wherein:

[0138] step S-15-1 designates that in case of the full automaticadjustment, the following processes are executed for each one of thewhole SQUID channels, and the channel under processing is referred to as“ch”;

[0139] step S-15-2 designates that the computed bias current and off-setvoltage are retained in memories named IBIAS and VOFF, that IBIAS andVOFF can save as many values as the number of the channels, with initialvalues being zero, and that an amplitude of signals to be savedtemporarily of the φ-V characteristic curve is defined as ΔV;

[0140] S-15-3 designates that by changing (scanning) bias current Ibfrom 0 to Ibias, which is designated in “Scan Parameter” frame in FIG.34, by ΔIbias step for each channel ch, a particular Ibias at whichamplitude ΔV of the φ-V characteristic curve becomes maximum is selectedas an optimal bias current IBIAS (ch) for the channel ch;

[0141] S-15-4 to -8 designate that for bias current between 0 to 1b,amplitude φ of the φ-V characteristic curve is obtained by the followingsteps: the external magnetic flux φ applied to SQUID of the channel chis changed (scanned) from 0 to next which is designated in “ScanParameter” frame of FIG. 34, by Δφ step, then the signals obtained byA/D conversion are saved, from which its maximum value Vmax and minimumvalue Vmin are obtained;

[0142] S-15-9 to -10 designate that if a difference between maximumvalue Vmax and minimum value Vmin is larger than ΔV, the value of IBIAS(ch) is replaced by Ibias, the value of VOFF (ch) is replaced by anaverage of the maximum value Vmax and the minimum value Vmin, and ΔV isreplaced by a difference between the maximum value Vmax and the minimumvalue Vmin, respectively, alternatively, if ΔV is greater than thedifference between the maximum value Vmax and the minimum value Vmin,the preceding value is retained.

[0143] S-15-11 designates that IBIAS (ch) and VOFF (ch) obtained byrepeating the above-mentioned steps of processing until its bias currentIb becomes the Ibias, become the optimal bias current and off-setvoltage for SQUID channel ch; and

[0144] S-15-2 designates that upon execution of the above-mentionedsteps of processing to every SQUID channels, the automatic adjustmentoperation is completed.

[0145]FIG. 23 shows the flow of the VOFF adjustment in step 18 of FIG.21, wherein S-18-1 designates that in case of the VOFF adjustment, thefollowing steps of processing is executed for each of every SQUIDchannels;

[0146] S-18-2 to -6 designate that by changing (scanning) externalmagnetic flux φ applied to SQUID of the channel ch from 0 to φext, whichis designated in the “Scan Parameter” frame of FIG. 34, by Δφ step, adifference (subtraction) between maximum value Vmax and minimum valueVmin in the signals obtained by A/D conversion are obtained;

[0147] S-18-7 designates that an optimal off-set voltage VOFF (ch) forthe SQUID channel ch is computed as a difference between the maximumvalue Vmax and the minimum value Vmin; and

[0148] S-18-8 designates that upon execution of the above-mentionedsteps of processing to the whole SQUID channels, the voff adjustment iscompleted.

[0149] According to the invention, the method and the apparatusfeaturing easy operation to allow for the processing and analysis ofmeasurement data of the biomagnetic or cardiomagnetic waveforms obtainedfrom the human body are provided. That is, because the waveforms ofsignals in response to biomagnetic fields produced in the human bodyunder measurement can be displayed with its designated time, its dataanalysis can be executed with reference to the time displayed on thescreen. Further, because a preferred reference waveform can be displayedrelating to the biomagnetic waves and/or its processed magnetic waves,the data analysis operation can be facilitated substantially.

[0150] Further, because the channel item frames are indicatedcorresponding to the channels currently displayed on the analysis datadisplay area, the channels displayed on the display area can be switchedby selection of the channel items in their respective frames. Stillfurther, because respective channels selected are displayed clearlydistinct from one another, the currently displayed maps can beidentified easily and visually.

[0151] Furthermore, because images of time integral map and/or themapping of distribution of propagation can be displayed, changingconditions or state of changes in the human body changing with time canbe learned precisely from their images.

[0152] Still further, in the averaging operation of the data for eachchannel, because the common base time is set as the reference, theaveraging operation becomes easier, and thus the noise in data obtainedin each channel can be eliminated easily.

What is claimed is:
 1. A processing method comprising the steps of:displaying on a screen a plurality of measurement positions of a patientat which biomagnetic fields emitted from a patient are measured;designating a measurement position at which information on a result ofits measurement is required to be displayed; and displaying informationon a result of measurement at the designated measurement position on thebasis of information recorded.
 2. A processing method according to claim1, wherein said screen includes: a display area for displaying saidmeasurement position, a display area for displaying information on thepatient; and a display area for displaying a result of measurement atthe designated measurement position.
 3. A processing method ofdisplaying information on a result of measurement at a plurality ofmeasurement positions of a patient on the basis of information recorded,comprising the steps of: displaying information on the result ofmeasurement on the display with a time axis of abscissa; and displayinginformation obtained on the basis of a result of measurement at adesignated time designated to display.
 4. A processing method accordingto claim 3, wherein the same comprises the steps of: displaying ahorizontal bar having a mark which designates a time position at whichinformation on the basis of the result of measurement is to bedisplayed; and designating said time position to be displayed by movingsaid mark along said horizontal bar.
 5. A processing method forobtaining a plurality of biomagnetic fields emitted from a patient at aplurality of measurement positions and executing processing of dataobtained as a result of such measurement at a specified measurementposition on the basis of data having been recorded, comprising the stepsof: setting a reference time condition; obtaining data at measurementpositions for a plurality of times under the set-up conditions and withreference to the reference time; and averaging a plurality of dataobtained at each measurement position.
 6. A processing method forobtaining a plurality of biomagnetic fields emitted from a patient at aplurality of measurement positions and executing processing of dataobtained as a result of such measurement at a specified measurementposition on the basis of data having been recorded, comprising the stepsof: displaying information on the result of the measurement obtained atsaid plurality of measurement positions by superimposing.
 7. Abiomagnetic field data mapping and display apparatus which measuresbiomagnetic fields emitted from a patient at a plurality of measurementpositions, and displays a map of biomagnetic field data which isobtained as a result of processing of the plurality of data, comprising:a process function display section for indicating process function itemsincluding measurement; and an analysis data display section whichproduces a waveform at least based on a biomagnetic field obtainedduring its measurement and which is formed during a designatedmeasurement time for displaying said waveform together with saiddesignated measurement time.
 8. A biomagnetic field data mapping anddisplay apparatus which measures biomagnetic fields emitted from apatient at a plurality of measurement positions, and displays a map ofbiomagnetic field data which is obtained as a result of processing ofthe plurality of data, comprising: a process function display sectionfor indicating process function items including measurement; and ananalysis data display section for displaying biomagnetic fields measuredand their processed magnetic field data, wherein the analysis datadisplay section includes a scroll bar and a scroll frame in a bottomportion thereof, said scroll frame movable along said scroll bar, andwherein a waveform displayed on said analysis data display section is apartial enlarged portion of a wave obtained during measurement timecorresponding to a time scale W of the scroll frame.
 9. A biomagneticfield data map display apparatus for displaying a magnetic field mapwhich is obtained by processing biomagnetic field data obtained at aplurality of positions of a patient, comprising: a process functiondisplay section for indicating process function items includingmeasurement; and an analysis data display section for displayingbiomagnetic fields measured and a processed magnetic field thereof,wherein the analysis data display section includes an auxiliary channelor a reference channel display area provided in a bottom portionthereof, said auxiliary channel or said reference channel relating tosaid analysis data.
 10. A biomagnetic field map display apparatusaccording to claim 9, wherein said reference channel displays areference wave which is one of biowaves related to biomagnetic fieldssuch as an electrocardiac wave, brain wave, blood stream wave, bloodpressure wave or the like, their displayed biomagnetic fields and theirprocessed magnetic fields.
 11. A biomagnetic field map display apparatusfor detecting biomagnetic fields emitted from a patient at a pluralityof measurement positions and displaying a map of a magnetic fieldsobtained, comprising: a process function display section for indicatingprocess function items including measurement; an analysis data displaysection for displaying biomagnetic fields measured and a processedmagnetic field map obtained by processing thereof; an operating regiondisplay section for indicating operating items for a biomagnetic fieldcorresponding to its processed magnetic field, wherein said analysisdata display section displays a biomagnetic field or a processedmagnetic field corresponding to a channel defined by a row and a column;said operating region display section displays a selection channel itemwhich is correlated with the channel defined by the row and column whichis displayed on the analysis data display section; means for selectingsaid selection channel item; means for displaying a biomagnetic field orits processed magnetic field corresponding to a selected channel item onsaid analysis data display section; and means for discriminating theselected channel item from other channel items.
 12. A biomagnetic fieldmap display apparatus according to claim 1, further comprising the stepsof: specifying a sampling time and its interval through a sampling itemdisplayed on said operating region display section; and displaying abiomagnetic field or its processed magnetic field obtained at thespecified sampling time and the interval on said analysis data displaysection.
 13. A biomagnetic field map display apparatus according toclaim 1, wherein said analysis data display section includes an area todisplay scroll frames for designating a measurement time scale, anddisplays a partial enlarged waveform of said biomagnetic field or saidprocessed magnetic field corresponding to said measurement time scale onsaid analysis data display section.
 14. A biomagnetic field mappingapparatus for detecting biomagnetic fields emitted from a patient usingmagnetic sensors of superconducting quantum interference devices(SQUIDS) at a plurality of measurement positions of multichannels, anddisplaying a map of magnetic fields as a result of their processing,comprising: a time integral data generation means for integratingbiomagnetic field data for a predetermined period of time, and executingcontour mapping of equivalent points of thus obtained data; and meansfor displaying a contour map of the time integral biomagnetic field dataobtained.
 15. A biomagnetic field mapping apparatus according to claim1, further comprising: means for forming a subtraction time integralmap, which obtains a subtraction between two time integral data whichare obtained over two different periods of time, and generates itssubtraction time integral map.
 16. A biomagnetic field mapping apparatusfor displaying a contour map of magnetic fields by measuring biomagneticfields measured at a plurality of measurement positions of a patientusing superconducting quantum interference devices (SQUIDs) andprocessing thus obtained biomagnetic field data, further comprising: apropagation data forming means for obtaining biomagnetic field data as apropagation data which propagates in a predetermined time scale; andmeans for displaying a map of distribution of propagation for the dataobtained by said propagation data forming means.
 17. A biomagnetic fieldmapping apparatus according to either one of claims 1-3, furthercomprising: a reference wave display means for displaying a referencewave relating to the biomagnetic fields obtained on a time axis; andmeans for changing a start time of computation by changing the positionof cursors provided movably on said reference wave.
 18. A biomagneticfield data mapping apparatus for displaying a contour map of magneticfields obtained by measuring biomagnetic fields emitted from a patientat a plurality of measurement positions thereof and processing thebiomagnetic fields thus measured, comprising: an analysis data displayarea for displaying measured biomagnetic fields and a map of magneticfields obtained by processing said measured biomagnetic fields; and anoperating region display area for displaying operating items to besubjected to data analysis, wherein said operating region display areadisplays operating items for entering an averaging mode and averagingconditions, and said analysis data display area displays biomagneticfields displayed on a time axis and an averaging time therefor, suchthat operation for setting the averaging conditions can be executedvisually simultaneous with the display of related waves.
 19. Abiomagnetic field map display apparatus according to claim 1, whereinsaid processed magnetic field is formed using the biomagnetic fieldsubjected to the averaging operation.
 20. A biomagnetic field mapdisplay apparatus according to claim 1, wherein said averaging conditionset-up operation includes designation of a channel, reference timesetting, off-set time setting, and/or adding time.
 21. A biomagneticfield map display apparatus according to claim 1, wherein a referencetime for the averaging operation is set at an intersection between thebiomagnetic waveform and a predetermined threshold therefor.
 22. Abiomagnetic field map display apparatus according to claim 1, wherein achannel subject to an averaging operation can be designated either byclicking a channel text frame in an averaging condition item menudisplayed on the operating region display area or by clicking a regionwhere a waveform of a preferred channel is displayed using a mouse. 23.A processing method for measuring biomagnetic fields on a patient at aplurality of measurement positions, and processing the same with respectto a designated measurement position on the basis of its informationstored, further comprising the steps of: setting a pitch of magneticfield contour mapping; and displaying a contour map of magnetic fieldobtained at a designated pitch.
 24. A processing method for measuringbiomagnetic fields on a patient at a plurality of measurement positions,and processing the same with respect to a designated measurementposition on the basis of its information stored, comprising the stepsof: displaying waveforms changing on a time axis; setting a plurality ofperiods of time for said waveforms on said time axis; and displayingcontour maps of magnetic field for the designated periods of time.